Device for ventilating engine crankcase



A ril 17, 1956 J. H. KRIECK DEVICE FOR VENTILATING ENGINE CRANKCASE 2Sheets-Sheet 1 Filed Oct. 22, 1952 INVENTOR. (fame: ff fl/c ATTORNEYSApril 1956 J. H. KRIECK 2,742,057

DEVICE FOR VENTILATING ENGINE CRANKCASE Filed Oct. 22, 1952 2Sheets-Sheet 2 Him,

INVENTOR. UZvmesHfl/ck c2 ZZZ} a 7 7 JTTORNEYQ United Sta e PatmfoDEVICE FOR VENTILATINGENGINE CRANKCASE James H. Krieck, Westport, Conn.Application October 22, 1952, Serial No. 316,196 3 Claims. (Cl. 138-45)tween the crankcase and the intake manifold, operable automatically'under the action of varying suction in said manifold to control gasflow from the crankcase above the sump to said manifold. Air is admittedinto the crankcase above the sump, and the venting action of the port ororifice between the crankcase and the intake manifold causes thecrankcase to be ventilated. The valve controlling this port or orificeautomatically varies the effective size of said port or orifice as thevacuum in the intake manifold varies, thereby minimizingvar'i'ations indraft conditions through the crankcase and into the en-' gine intakeresulting from this variation in the intake vacuum. I i o Theoperationof the crankcase ventilating device of they general type referred toprevents build-up of pressure in: the crankcase, and as the air is drawnthrough manufacture and ease in 2 the cleaning and servicing of saidvalve parts.

Various other objects of. the invention are apparent from the followingparticular description and from inspection. ofthe accompanying drawings,in which:

Fig. 1 is a s'ijdeview of the internal combustion engine ofan.autoniobile,fparts of said engine being shown broken 'away' to exposethe interior of the crankcase, said engine being shown in connectionwitha crankcase ventilating system embodying the present invention; thevalve, filter and trap unit forming part of said system being shown inperspective within a. circle and magnified for clarity; 3

' Fig. 2 is a vertical section of the valve, filter and trap unitembodying the present. invention; 9

Figs. 3. and 4,are sections of the'valve part of the crank.- caseventilating system taken along lines 3-3 and. 44.

' respectively of Fig. 2;

, Fig. 5 is an end view. of the valve part of the crankcase'ventilatingsystem taken along lines 5-5 of Fig. 2; and

Fig. 6.shows in vertical section a valve device alone secured directlyto' the intake manifold of an internal combustion engine in a simplerform of crankcase ventilating system embodying the present invention.

' Referring to Fig. 1 of the drawings, the crankcase ventilating systemof the present invention is shown applied to the internal combustionengine 10 of an automobile "having theusual crankcase 11, the road drafttube 12 connected to the crankcase but having its discharge endpartially shut off by a plug or cork 13 to adapt the engine to saidcrankcase ventilating system, the intake manifold 1 4' for delivering anexplosive mixture to the cylinders of theengine and "the carburetor 15havingan outlet connection to the intake manifold and an inletconnectionto an air strainer 16.

' The plug or cork 13 has a surface V-groove or a hole the crankcase andinto the intake, it carries with it the valve device described has afilter and a trap associated" therewith'to remove the heavy particlesand impurities in these-vapors-or gases, such as heavy carbon, sludgeand the like, before delivering the' vapors into the engine intake; 'Theresulting clean volatile oily vapors containing moisture or steamentering the intake are beneficially consumed in the explosion chambers.As a result of the operation described, there are provided as benefitsconstant crankcase ventilation, continuous automatic upper enginelubrication, better piston seal and freervalve action, extraction of oildiluting ingredients, detection of leaky or porous cylinders, heads andgaskets and reduction of sludge formation.

- One object of the present invention is to provide a crankcaseventilating valve device of the general type de scribed, which isconstructed to prevent the movable valve member from getting stuck dueto the collection of gummy vapors ladenwith varnish, sludge, etc, whichalfords minimum of surface contact between the movable valve member andthe valve case and is constructed to prevent wear and/or distortion ofthe orifice by the contact action of any valve parts rigid with saidmovable valve member, which is constructed to aiford gradual variationin the effective size of the valve port or orifice as the intake suctionvaries, which has a movable valve member exposed to atmospheric pressureand presenting a comparatively large surface to said pressure, assuringthereby more positive action of the valve, and which is simple ofconstruction and is made up of a minimum number of valve parts, therebyaffording economy of extending therealong for two purposes. I Theopening formed'thereby in the plugor cork 13 prevents the pressure inthe crankcase 11. from building up, in case the valveftrap and filterunitof Fig. 2 to be described, should fill up sufficiently to hinderfree flow'of gases there through, and serves as admin to preventcollection of condensation in the road draft tube 12 and the return ofthis condensation to the crankcase.

When no road draft tube is provided, then a T-connection may be providedin the valve inspection or cover 1 plate of the crankcase or whereverthe attachment to the crankcase is made. and thus provide for a branchpipe which is the equivalent of the road .draft tube and a branch leadto the intake of the valve, trap and filter unit of Fig. 2 to bedescribed.

For ventilating the crankcase 11, there is connected to said crankcasenear one end and above the sump an oil therein, an air inlet pipe 17open to the atmosphere throughanair filter 18. Near the other end of thecrankcase 11, there is mounted between said crankcase and the intakemanifold 14, a valve, trap and filter unit 20 operable to remove theimpurities from the vapor current induced towards the intake manifold bythe vacuum therein and to control the flow of the purified'vapors intosaid intake manifold. Referring to Figs. 1-5, this valve, trap andfilter unit 20 comprises a valve 21 having a valve body or case 22consisting of a main cylindrical section 23, a conical shoulder section24 defining a conical valve seat 25 and a neck section 26 with a throat27 defining a cylindrical valve orifice 28. Threaded to the upperdischarge end of the neck section 26 of the valvecase 22 is a bushing 29for thescrew attachment thereto of a hose 30 connected to the intakemanifold 14.

Movable in the valve case 22 is a valve piston 31, which in mountedposition of the "entire unit 20 extends vertically 3 vertically inresponse to the inductive action of the vacuum in the intake manifold 14transmitted to the valve 21 through the hose 3%). This valve piston 31is substantially of square cross-section to define four similar sides 32inquadrature relationship, these sides being flat as shown or concave.At its upper end, the valve piston 31 has an axial conoidal plugextension 33 of reduced diameter tapering upwardly or outwardly, andfitted into the orifice 2 8 to vary its effective opening with changesin lift.

The diagonal dimension of the valve piston 31 between opposite cornersis slightly smaller than the internal diameter of the main cylindricalcase section 23, so that these corners reach the internal wall of saidcase section and are confined thereby against transverse movement. Thevalve piston 31 thereby has a snug slide fit in the cylindrical casesection 23, permitting said piston to move freely up and down accordingto the degree of vacuum in the intake manifold 14 with minimum offriction resistance from the internal wall of said case section but withlittle or no transverse movement.

The orifice 28 is large enough so that even when the valve piston 31 isin uppermost limiting position with the upper edge of said pistonseating against the internal conical surface 25 of the shoulder casesection 24, said orifice is not entirely closed by the plug 33 on saidpiston but defines a clearance in said orifice around said plug. Thevalve piston 31 has such little transverse play in the cylindrical casesection 23, that the plug 33 cannot contact the wall of the orifice as aresult of such transverse play, even in the upper limited position ofthe valve piston described.

The sides 32 of the valve piston 31 whether flat or substantiallyconcave extend chordally of the cylindrical inner wall surface of themain case section 23 and define thereby with said surface substantiallysegmental spaces 37 constituting the passageways for the crankcasevapors in their transit through the valve 21. Even in upper limitedposition of the valve piston 31, with said piston seated against theinner conical surface 25 of the shoulder case section 24, the upperseating edges of said valve piston define with said surface segmentalspaces, thereby maintaining uninterrupted vapor flow through the valve21 at all times regardless of the position of the piston. Where thesides 32 of the valve piston 31 are concave instead of fiat as shown,the-passageways defined between said piston sides and the innerperipheral surface of the valve case 22 will be of largercross-sectional area.

As the vacuum in the intake manifold 14 is reduced, the valve piston 31drops by gravity until a limiting position is reached. To so limit thedrop in the valve piston 31 without closing the lower end of the valvecase 22, there is provided a stop pin 40 extending diametrically throughthe main case section 23 near its lower end. To prevent the valve piston31 from adhering to this stop pin 40 as the result of gummy or stickycollections thereon, the amount of contact surface between the pistonand the stop pin is reduced to a minimum by providing a recess 41 shownof conical form in the lower end of the piston. By this construction,the stop pin 40 in lower limited position of the valve piston 31 engagesthe valve piston at only two diametrical regions at the foot of therecess 41.

The valve 21 is associated with a filter and a trap to form the unit 29,and to that end, the valve is enclosed in a filter housing 50 carrying abracket 51 by which the unit may be mounted on and attached to theengine casing or frame. A cover plate 52 is releasably secured to theupper end of the housing 50 by means of spring clips 49 hinged to thesides of said housing. Enclosed in the housing 50 and encircling thelower open end of the valve case 22 is a vapor filter element 53constructed of suitable design, and made for example of woven textile.In the specific design shown, this filter element is cylindrical and hasa bottom impervious rigid wall 54 and a top impervious rigid wall 55with a center sleeve 56 threaded on the outside of the main valve casesection 23. The filter element 53 is smaller in external diameter thanthe internal diameter of the housing 50 to define an annular clearance57 for the passage if crankcase vapors therein discharged from a lowertrap 58 to be described.

The trap 58 forming part of the unit 20 is located on the bottom of saidunit and comprises a glass jar 60 releasably retained in positionagainst the lower end of the filter and valve housing 50 by a pair ofspring hooks 61 hinged at their upper ends at 62 to diametricallyopposite sides of the housing and having their lower offset endsreleasably caught onto the bottom of the jar. The upper open end of thejar 60 may, if found desirable, be closed by a bafiie plate 63 having acenter hole 64 through which one leg of an angle pipe 65 extendsvertically downward with a clearance 66, the other leg of said pipeextending horizontally above the baffie plate and terminating in a tip67 outside the housing 50 suitable for the attachment of a hose 63connecting into the crankcase 11, as for example through the closed roaddraft tube 12, as shown in Fig. 1.

In the operation of the crankcase ventilating system shown in Figs. l-S,during operations of the engine 10, a vacuum is maintained in the intakemanifold 14 preventing build-up of pressure in the crank case 11 andcausing fresh air to be drawn into the crankcase through the filter 18and the pipe 17. The air passing over the sump or oil in the crankcase11 carries the vapors from said crankcase through the hose 68, throughthe angle pipe 65 and into the glass jar 60. The heavy impurities in thevapors such as water, heavy carbon, sludge, dirt and the like drop bygravity into the jar 60 accumulating at the bottom thereof. The lighterimpurities, in addition to the volatile fumes, moisture or steam andlubricating film travel upwardly through the clearance 66 in the bafileplate hole 65 around the angle pipe 65 and into the housing 56 and passtherein through the filter 53 where the light solid impurities areintercepted. The strained and purified gases are then drawn through thelower open end of the valve case 22, along the passageways 37 on thesides of the valve piston 31, through the restricted orifice 28, throughthe hose 30 and into the intakemanifold 14. The vapors admitted therebyinto the intake manifold 14 will contain minute particles of oil or oilvapor which will eventually be deposited in the valve stems, compressionrings, cylinder walls and cylinder pistons, thus greatly aiding in theirlubrication. Moisture in the vapors admitted into the intake manifold 14from the crankcase 11 will be deposited in the explosion chambersforming steam and thus reducing the formation of carbon. Cleaned fuelgases mixed with the air drawn into the intake manifold 14 in the mannerdescribed, enrich the explosive mixture and thereby improve theefficiency and performance of the engine.

The valve 21 automatically controls the flow of vapors into the intakemanifold 14 according to the suction in said manifold. In the absence ofthe valve 21, as the suction in the intake manifold 14 increases, theamount of vapors drawn from the crankcase 11 increases and may overloadsaid manifold. To offset the effect of varying suction in the intakemanifold 14, the valve 21 is provided, operable to decrease itseffective orifice opening as the vacuum in said manifold increases. Theamount of vapors drawn into the intake manifold 14 remains therebysubstantially constant, or may have any desired predeterminedquantitative relation to the degree of vacuum in said intake manifold,according to the degree of taper of the valve plug 33. Since the valveplug 33 is conical in shape, variations in effective orifice openingthrough which said plug extends is gradually progressive and affordsgradual volumetric variation at a predetermined rate. Also, any dirtcollecting in the orifice 28 around the plug 33 is forced out of theorifice by the pushing action of the flaring sides of said plug as saidplug is moved upwardly, thereby maintaining said orifice clear of dirt,even without contacting said plug with the wall of said orifice.

Since the valve piston 31 is restrained against lateral movement, thevalve plug 33 does not contact the wall of the orifice 28, so that thisorifice does not become worn and enlarged and the valve plug does notwear out and become reduced in size.

Because of the peculiar shape of the valve piston 31, no pockets arepresented thereby in which dirt and gum may collect. Moreover, becauseof this piston shape and the conical shape of the seat 25, this pistonat no time completely closes the valve 21 against flow therethrough.

Also, the lower end of the valve case 22 being entirely open except forthe stop pin 40, this affords comparatively small areal contact betweenthe valve piston 31 and its stop and thereby assures against thesticking of the piston in its lowermost stopped position by thecollection of gum and the like in the region of contact. Moreover, thisopen ended construction of the valve case 22 exposes the entire end ofthe valve piston 31 of comparatively large area to the atmosphericpressure from the crankcase 11, thereby improving the pressure liftingaction on said valve piston and rendering'said piston more positive inaction.

The segmental passageways 37 along the sides of the valve piston 31 aresufficiently large compared with the orifice clearance around the valveplug 33, to assure a smooth steady flow of vapors through said clearancein all positions of said valve piston.

The valve 21 is made essentially of two simple parts 22 and 31 which areeconomical to manufacture and which may be easily taken apart forcleaning and servicmg.

Although the valve 21 is shown in Figs. 1-5 associated with the filter53 and the trap 58 to form the unit 20, as far as certain aspects of theinvention are concerned, the valve may be employed between the crankcase11 and the intake manifold 14 without the auxiliary filter and trapdevices. In Fig. 6, the valve 21a similar to the valve 21 is shownemployed in the modified manner described. This valve 21a has the necksection 26a of its case or body 22a threaded into one end of an elbow70, the other end being screwed into the intake manifold 14. The lowersection of the valve case 22a has a direct connection to the closed roaddraft tube 12 through a pipe 71 having an enlarged sleeve 72 at one endthreaded over said valve case and having its other end secured to saiddraft tube by a screw connection. In all other respects, the valve 21ais the same as the valve 21 in the construction of Figs. 1-5.

While the invention has been described with particular reference tospecific embodiments, it is to be understood that it is not to belimited thereto but is to be construed broadly and restricted solely bythe scope of the appended claims.

What is claimed is:

l. A valve structure adapted to be mounted in a conduit through which agas passes at varying rates which affect the operation of a valve tocontrol the quantity of gas passing through said conduit, thecombination of a valve casing connected in said conduit, said casinghaving a small aperture in the top thereof connecting into said conduitand an aperture at its base connected into said conduit, said casingbeing tapered at the top to form a stop at a point below said aperture,a pin across the bottom portion of said valve casing to hold a valvepiston when in lowermost position, a valve piston mounted in said casingand adapted to be floated therein only by reason of the variations inpressures of gas passing through said conduit, said valve piston havingfour edges along its side for engaging the side of said casing forguiding said piston, said piston having a tapered portion mounted at thetop thereof and movable into and out of said aperture without touchingthe side walls thereof, said tapered portion being of varying diametersthroughout its length to afford variations between minimum and maximumopenings of said aperture to vary the effective opening thereof.

2. In combination, a valve casing mounted in a conduit having gaspassing therethrough at varying rates and volumes, said casing havingopenings at each end and with one i of said openings forming a smallorifice, a piston mounted in said valve casing and being automaticallymovable therein in response to pressure changes of gas flowing throughsaid casing, said piston having a tapered portion which extends intosaid orifice without touching the walls of said orifice, said taperedportion and said orifice cooperating to control the quantity of flow ofgas through said orifice as said tapered portion moves into and out ofsaid orifice, a shoulder formed in said casing near said orifice forengaging a part of the upper portion of said piston to limit themovement thereof in one direction, said tapered portion of said pistonbeing in non-engagement with the walls of said orifice at all times whensaid piston engages said shoulder thereby controlling the amount of gasirrespective of rate of flow of said gas to pass around said taperedportion and through said orifice, the cubic capacity of said casingadjacent and above said shoulder when said valve piston is in itsuppermost position being greater than the area across said orifice whenthe valve is in its uppermost position.

3. In combination a valve casing, mounted in a conduit having gaspassing therethrough at varying rates, said valve casing having asubstantially cylindrical inner wall surface and having a shoulderformed therein near its upper end and having an orifice adjacent saidshoulder, a piston mounted in said valve casing and automaticallymovable up and down therein in response to pressure changes in the gasflowing therethrough, said piston having square edges slidable along theinner wall surface of said casing for maintaining axial alignment ofsaid piston in said valve casing, said piston having indented side wallsbetween said edges to provide gas passageways leading to said orifice,said piston having an elongated tapered portion integral with the topthereof and constructed with a taper throughout its length and extendingthrough said orifice to continually vary the opening of said orificewith pressure changes in said conduit by moving its tapered surface toeffectively vary the quantity of gas moving through said orifice, saidelongated tapered portion always remaining out of contact with the wallsof said orifice and never closing said orifice tightly, and stop meansadjacent the bottom edge of said casing for limiting the downwardmovement of said piston, the bottom of said valve piston being concaveand only engaging said stop means at least at one point of engagementtherewith, thus preventing sticking of said valve piston on said stop.

References Cited in the file of this patent UNITED STATES PATENTS1,049,992 Catchings Jan. 7, 1913 1,100,761 Mueller et al June 23, 19141,242,003 Lewis Oct. 2, 1917 1,498,399 Parker June 17, 1924 1,529,384Adams Mar. 10, 1925 1,990,657 Krieck Feb. 12, 1935 2,093,035 DaviesSept. 14, 1937 2,359,485 Lowther Oct. 3, 1944 2,367,662 Baxter et al.Jan. 23, 1945 2,450,864 Calloway Oct. 5, 1948 2,550,373 Ortlofi et alApr. 24, 1951 FOREIGN PATENTS 437,161 Great Britain Oct. 24, 1935

